Yeah, I thought of this, but the reason my motherboard died was because of swollen capacitors. I checked out an identical computer for sale locally (good price) but it was also suffering from swollen capacitors (just hadn't failed yet). So I was very wary of sticking with the same motherboard, even though I was very happy with the computer while it had functioned.
Have a look at one of those Re-Cap services, may cost you $50 but will be like new.
Chris